Pressure-gage.



No. 697,623. Patented Apr. l5, |902. F. H. HASKELL.v

PRESSURE GAGE.

(Applicatnn led Jan. 17, 1902.)

(No Model.)

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UNITED STATES PATENT OFFICE.

FRANK H. HASKELL, OF BOSTON, MASSACHUSETTS.

PRESSURE-GAGE.

SPECIFICATION forming' part of Letters Patent No. 697,623, dated April15, 1902.

l Application tiled January 17, 1902. Serial No. 90,167. (No model.)

To all whom, it may concern.:

Be it known that I, FRANK H. HAsKELL, o Boston, in the county of Suffolkand State of Massachusetts,have invented certain new and usefulImprovements in Pressure-Gages, ot' which the following, taken inconnection with the accompanying drawings,is a speciflcatiom Myinvention relates to pressure-gages, and has for its object a reductionin the number of joints that are subject to wear, thereby reducing to aminimum the liability of imperfect indication by the indexfinger, toprovide suitable adjustments for the index-operating mechanism, and torender it practical to use a heavier Bourdon spring-tube to indicate agiven pressure than has heretofore been the practice; and it consists incertain novel features of construction, arrangement, and combination ofparts,which will be readily understood by reference `to the descriptionof the accompanying drawings and to the claims hereto appended and inwhich my invention is clearly pointed out.

Figure 1 of the drawings is an lelevation of apressure-gage embodyingmy'invention with the dial, the glass front, and the glass-holdingringremoved. Fig. 2 is a section on line 2 2 on Fig. 1 with the dial,the glass, and the glass-holding ring in position. Fig. 3 is a similarsection on line 3 3 on Fig. 1. Fig. 4c is a vertical longitudinalsection of the socket and stand, in which is mounted' the rack-op-yeratinglever,drawn to an enlarged scale. Fig. 5 is an elevation of therack and pinion for operating the index-finger, also drawn to a stilllarger scale. Figs. 6 and 7 are respectively an elevation and a plan ofthe ilexible connecting-rod for connecting the movable end of theBourdon spring-tube to the rackoperating lever, and Figs. 8 and 9 arerespectively an elevation and an inverted plan of the adjustableconnection of the rack-operating lever and the rod connecting theBourdon spring.

In the drawings, 1 represents the main body of the casing, 2 is thedial, 3 is the glass front, and 4 is the glass-holding ring, all ofusual construction.

The casing 1 has secured therein the socket 5, having formed in onepiece therewith the arm y6 and the ear 7, said arm and ear havingmounted in bearings therein the shaft 8, upon which is firmly securedthe lever 9, through which a 4reciprocating movement is imparted to therack 36. The ear 7 has a hole formed therein of a diameter suflicientlylarge to permit the shaft S to be passed upward through the same at anangle to a sufficient distance to permit its lower journal to be droppedinto the bearing therefor in the arm 6. The hole in said ear 7 isinternally threaded and has fitted thereto the threaded bushing 11, inwhich the upper journal of the shaft Sha's its bearing,said bushingbeing readily adjustable vertically to take up any wear that may occurupon the shoulders of saidfshaft. VThe shaftS is arranged in as nearproximity to the socket-stand 5 as may be practicableV in order toincrease the length of the lever 9,` whereby less movement of themovable end' of the Bourdon spring-tube will be required,

and consequently a heavier spring maybe.,k

employed.

The Bourdon spring-tube 12, of ordinary con struction, has one endfirmly set in the socket 5 in the usual manner and has formed upon orysecured to its other end the platev 13, in which isset the slotted stud14. and the clamping-screw 15, which passes through an eye in one end ofthe connecting-rod 16 and firmly secures it to said plate 13, said rodbeing prevented from moving about said screwrl by `being embraced by theforked stud 14, as

shown in Figs. 1 and 3. The rod 16 is made of such material and of suchsize as to render it suflicientl y flexible to enable it to springbetween its two connections as the point of connection thereof to therack-operating lever moves through an arc of a circle,and the movableend of the spring-tube is moved outward and upward Without moving aboutvits connection to said lever and has its other end secured to the plate17 by means of the forked or slotted stud 18and the clampingscrew 19,said plate 17 having formed therein a slot 2O and is adjustably securedto one arm of the plate 21 by means of the clampingscrew 22 and thesteady-pin 23, theother arm of the plate 21 having formed therein theslot 24 and is adj ustably secured tothe lever 9 by means of theclamping-screw 25, which passes through said slot andA is screwed intothe le- IOO ver 9, and the steady-pin 2G, setin said lever andprojecting into said slot in said plate 21, all as shown in Figs. 1, 2,8, and 9.

The lever 9 has adj ustably secured to its movable end theextension-plate 27 by means of the clamping screw 28, which passesthrough a slot 29, formed in said extension, and screws into said lever,and the steadypin 30, set in said lever and projecting into said slot29, as shown in Figs. 1 and 2.

The arm 6 of the socket 5 extends to the centerof the casing l and hassecured thereto the stand 31, in suitable bearings in which is mountedin a well-known manner the spindle 32, upon the outer end of which ismounted the index-finger 33, between the dial 2 and the glass front 3,in a well-known manner. The spindle 32 has firmly secured thereonbetween its two bearings in the stand 3l the pinion 34, and said standhas formed therein a suitable guideway or bearing 35 for the rack 36,one end of which is pivoted to the extension of the lever 9 at 37. Thepinion 34 is provided with teeth, the ends of which are rounded or formarcs of circles, and the bottoms of the spaces between the teeth of therack are in the form of arcs of circles, which are intended to restdirectly upon the ends of the teeth of the pinion,said rack being heldin said position of contact with said pinion by the set-screw 38 and thelight spring 39. As the movable end of the lever to which said rack ispiv- 'oted moves in the arc of a circle, it follows that the angle ofmovement of said rack varies in diiferentpositions of said lever, sothat the pivoted end of said rack rises or falls as it is moved to andfro by the vibrations of said lever. To enable the rack at all times torest upon the teeth of the pinion and still permit a free movement ofsaid rack and pinion, I form the teeth of said rack in the shape of aletter V with a slightly-rounded point, and the upper side of the rack,against which the screw 38 bears lightly, is curved from a to b, so thatthe distance between the rounded bottom of the space between any twoteeth of the rack and the upper surface ofsaid rack shall be the samewhen measured on a line at the same angle to the pitch-line of said rackwhich a line drawn through the axis of the pinion and the center line ofthe screw 38 bears to said pitch-line when the rack is moved to bringeach successive racktooth between said pinion and the screw 38, asindicated by dotted lines c, d, e, f, and g on Fig 5. Theextension-plate 27 has secured thereto the light curved spring 39, whichbears lightly upon the upper surface of the rack to press it lightlydownward upon the pinion.

The advantages of my invention are as follows: By mounting the fulcrnmof the lever which operates the rack in near proximity to the socket 5and connecting the rod 16 to said lever between its fulcrum and itsmovable end a greater leverage of said lever is obtained in a given sizeof case than when the connection of said rod and lever is between thefulcrum of said lever and the socket, as heretofore practiced, andconsequently a heavier Bourdon spring-tube is required, which is anadvantage because of the greater durability of said spring-tube. By theadjustable connection of the rod 16 to the lever 9 the leverage of saidlever may be readily varied to meet the conditions of any particularcase, and the normal position of the rack may be varied to suit varyingconditions, and by the adjustment of the exten sion-plate 27 anothermeans of varying the leverage of said lever 9 is provided to suitdifferent conditions. By making the rod 1G of such material andconstruction as to render it flexible between its two ends and securingits two ends to the spring-tube 12 and the lever 9, so that there is nomovement of said rod about its connections to said parts, two points ofwear that heretofore have caused more or less trouble are eliminated,and by mounting the upper journal of the shaft in a threaded bushingfitted to a threaded hole in the ear 7 of the socket the socket 5, armG, and the ear 7 may be made in one piece and the shaft 8 may be readilyplaced in position and said bushing may be readily adjusted to take upany endwise wear of the shoulders of said shaft. By the construction ofthe rack and pinion as hereinbefore described a close contact of saidrack and pinion is maintained, and though the position of the rackrelative to a horizontal plane is constantly changing as it reciprocatesthere is, no binding of said rack in its bearings, and it rests in allpositions of its reciprocation upon the teeth of the pinion, and alllateral play or rattling of said rack in its bearing is obviated.

The connecting-rod 16 may be made of spring-wire, as shown, or of tlatribbon of spring material.

The operation of my inven tion will be readily understood from theforegoing without further description here.

Instead of extending the arm 6 to the center of the casingit may extendonly farenough to form an ear, in which the lower journal of the shaft 8has its bearing, and the stand 3l may be secured directly to the bottomor back of the casing, if desired.

What I claim as new, and desire to secure by Letters Patent of theUnited States, is-

l. In a pressure-gage, the combination with a single Bourdon-gagespring-tube extending around approximately three-fourths of a circle; ofa tube-supporting socket; a shaft-supporting stand formed in one piecewith said socket; an index-carrying shaft; a pinion mounted on saidshaft; a rack engaging said pinion; a rack-operating lever fulcrumed innear proximity to said socket; and a rod havingone end pivoted directlyto the movable end of said spring-tube and its other end pivoted to saidlever between its fulcrum and its movable end.

2. In a pressure-gage, the combination with IIO a Bourdon spring-tubeextending around approximately three-fourths of a circle; of aspring-tube-supporting socket; a shaft-sup porting stand, formed in onepiece with said socket, the outer ear of said stand VbeingPV providedwith a threaded hole therein of greater diam eter than said shaft; ashaft pro'- vided With shouldered journals, and mount-` ed in saidstand; a threaded tubular bushing iitted to the threaded hole in saidouter ear and forming a bearing for the outer journalv of said shaft; arack-operating lever mounted on said shaft; and a rod pivoted at one endto the movable end of said spring-tube, and

at its other end to said lever between its fulcrum and its movable end.

3. In a pressure-gage, the combination with a lBourdon spring-tube, asocket for supporting the same, 'a dial, an index-ringer, its spindle, apinion mounted on said spindle, and a rack and lever for rotating saidspindle, of a flexible connection between the movable end of the Bourdonspring and said pinion-operating lever, the ends of said flexibleconnection being rigidly clampedone tosaid spring, and the other to Saidlever.

4. Ina pressure-gage, the combination with an index-finger, its spindle,a pinion mounted o n said spindle, a Bourdon spring-tube its supportingsocket and stand, a lever mount-V ed in bearings in said (stand, and areciprocating rack operated by said lever, ofthe.

plate 13 firmly secured to the movable end of said spring, and providedwith the slotted stud 14, and the clampingfscrew 15; the twoarmed plate21, adjustably secured to the rack-operating lever; the slotted plate 17adj ustably secured to the plate 21, and provided with the slotted stud18 and the clampingscrew 19; and theflexiblevconnection 16, providedwith an eye at each end to receive the clamping-screws'l and 19, saidiiexible connection, being ,embraced by the slotted studs 14 and 18, innear proximity to the clampingscrews 15 and 19 respectively;

5. In a pressure-gage, the combination with a Bourdon spring-tube, itsvsupporting-socket, and a shaft-supporting etand, a lever fulcrumed insaid'stand, a connection between 'the movable end of said spring-tubeand said tact With the teeth ofsaid pinion.

6. In a pressure-gage the combination with a Bourdon spring-tube, itssupporting socket and stand, a leverrfulcrumed in said stand, aconnection between the movable end of said spring-tube and said lever,anindex-iinger, and its spindle, of the pinionu34 provided with teethhaving rounded ends; andthe reciprocating rack 36 provided With V-shapedteeth with the spaces between said teeth curved to the arc of a. circle,and' its upper surface curved longitudinally to compensate for the riseand fall of itspivoted end, due to the arc described by the movable endof its operating-lever.

. In testimony whereof I have signed my name to this specification, inthe presence of tw'ousubscribing Witnesses, on this 15th day of January,A. D. 1902.

FRANKl H. HASKELL.

W'itnesses:`

y N. O. LoMBARD,

WILLIAM W. WEBB.`

